<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Class与ID的差异</title>
  <style>
    #myHeader {
      background-color: lightblue;
      color: black;
      padding: 40px;
      text-align: center;
    }

    .city{
      background-color: tomato;
      color: white;
      padding: 10px;
    }
  </style>
</head>
<body>

<h1 id="myHeader">My Cities</h1>

<h2 class="city">London</h2>

<h2 class="city">Paris</h2>
<p>Paris is the capital of France.</p>

<h2 class="city">Tokyo</h2>
<p>Tokyo is the capital of Japan.</p>

</body>
</html>